Embodiments of the invention relate generally to devices and methods for assigning priority to messages or transmissions in a network.
The need and desire for users, such as consumers, single home small office (SOHO) users, small businesses, etc., for telecommunications services continues to increase dramatically. Users desire faster Internet connections, facsimile service, telephone service, etc., in order to take advantage of the connectivity that each of these services provides. In response, many telecommunications companies have created a large amount of bandwidth capacity on long-haul transmission routes (the backbone network infrastructure) through the use of fiber-optic networks, which can transmit data at speeds in excess of 10 gigabytes per second (Gbps). A disconnect exists, however, between the backbone networks and the local loops of local exchange carriers. The connection between the local exchange carriers and the end users, particularly smaller users, is still mostly twisted pair copper cable instead of high-speed fiber-optic cable. This failure to provide high-speed connections for “the last mile” has resulted in a bandwidth bottleneck between the increasing data needs of users and the high-speed backbone network.
One solution to this bottleneck is to lay high-speed fiber-optic cable directly out to individual users. This solution is both very expensive and slow to implement. Another solution is to utilize existing telephone lines, such as with DSL or other high-speed connections. These solutions, however, are generally expensive and have upper physical limits on their bandwidth capacity.
Another solution to the bottleneck is to utilize wireless telephony. Wireless telephony provides voice data links between users of mobile devices and fixed devices on a network. It gives users using a wireless phone or other wireless device mobility without regard to how they are actually connected to the network. This is done by providing access points or base station units that can hand off the connections of mobile devices without interruption of the service. 2G (second-generation) digital mobile phone service such as the Global System for Mobile Communications (GSM), EIA/TIA-136 Time Division Multiple Access (TDMA), TIA-IS-95 Code Division Multiple Access (CDMA), and the AMPS (analog mobile phone service) are examples of such telephone networks. Wireless telephony, however, is plagued by limited bandwidth, which is particularly problematic for higher bandwidth applications such as use of the Internet.
A more recent solution to the bottleneck problem is a fixed wireless network, which may also be known as a wireless local loop (WLL). Fixed wireless networks are the infrastructure used to provide radio (microwave) transmissions between two or more stationary points. Fixed wireless networks can provide high-speed, highly reliable connections between users and a high-speed backbone network, bypassing the “last mile” bottleneck using a broadband wireless connection. The fixed wireless network is generally built around a number of radio base stations (bases), each connected by microwave, coaxial cable or fiber-optic back-hauls to one or more central office switches. The base is connected to each user remote units (RU) via a radio link. Each RU would have a directional antenna aimed directly at the base and attached outside their building. The fixed wireless network therefore creates a link between RU's and the backbone network via a base, allowing access to the Internet, a public switched telephone network (PSTN), etc.
One problem with fixed wireless networks is that as the number of users increase for each base, the current protocols become increasingly inefficient because of collisions between RU's accessing upstream channels and resulting “backoffs”. Current systems implement a Carrier Sense Multiple Access with Collision Detection (CSMA/CD) protocol. In the CSMA/CD protocol, all devices attached to a network listen for transmissions in progress before starting to transmit. If two or more devices begin transmitting at the same time and their transmissions “crash” into each other, each “backs off” before again attempting to transmit. While the CSMA/CD protocol does allow for multiple RU's accessing a single channel, the number of backoffs, and thus the inefficiencies and delays, increase as the number of RU's increase.
Another problem with existing fixed wireless networks is that current protocols do not provide any method for differentiating between RU's with respect to their priority. For example, higher priority RU's may collide with lower priority RU's and be delayed for an unacceptably long time.
Expense, inconvenience, and problems with scalability plague current solutions to the problem of the “last mile”. Users and telecommunication providers alike continue to seek a more efficient and effective ways of providing telecommunications services to users without direct access to a high-speed backbone.
In the drawings, the same reference numbers identify identical or substantially similar elements or acts. To easily identify the discussion of any particular element or act, the most significant digit or digits in a reference number refer to the Figure number in which that element is first introduced, e.g., element 102 is first introduced and discussed with respect to FIG. 1.
Note that the headings provided herein are for convenience and do not necessarily affect the scope or interpretation of the invention.